.TH std::stack::top 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::stack::top \- std::stack::top

.SH Synopsis
   reference top();
   const_reference top() const;

   Returns reference to the top element in the stack. This is the most recently pushed
   element. This element will be removed on a call to pop(). Effectively calls
   c.back().

.SH Parameters

   \fI(none)\fP

.SH Return value

   Reference to the last element.

.SH Complexity

   Constant.

.SH Example


// Run this code

 #include <iostream>
 #include <stack>

 void reportStackSize(const std::stack<int>& s)
 {
     std::cout << s.size() << " elements on stack\\n";
 }

 void reportStackTop(const std::stack<int>& s)
 {
     // Leaves element on stack
     std::cout << "Top element: " << s.top() << '\\n';
 }

 int main()
 {
     std::stack<int> s;
     s.push(2);
     s.push(6);
     s.push(51);

     reportStackSize(s);
     reportStackTop(s);

     reportStackSize(s);
     s.pop();

     reportStackSize(s);
     reportStackTop(s);
 }

.SH Output:

 3 elements on stack
 Top element: 51
 3 elements on stack
 2 elements on stack
 Top element: 6

.SH See also

   push inserts element at the top
        \fI(public member function)\fP
   pop  removes the top element
        \fI(public member function)\fP
